<!-- 实现一个页面头部固定，但是左侧菜单和内容是可以滚动的布局 -->
<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        html,
        body {
            height: 100%;
            margin: 0;
            padding: 0;
        }

        .wrap {
            background: #a00;
            height: 100%;
            display: flex;
            flex-direction: column
        }

        .hd {
            background: #2980b9;
            flex: 0 0 60px;
            /* flex布局中的flex---->flex-grow、flex-shrink、flex-basic的缩写 */
        }

        .bd {
            display: flex;
        }

        .left {
            background: #ecf0f1;
            border: solid 5px #e67e22;
            width: 200px;
        }

        .content {
            background: #ecf0f1;
            border: solid 6px #f1c40f;
            flex-grow: 128389;
            overflow: auto;
        }
    </style>
</head>

<body>
    <div class="wrap">
        <div class="hd">头部</div>
        <div class="bd">
            <div class="left">左侧</div>
            <div class="content">
                <div style="height: 2050px;overflow-y: auto;">内容</div>
            </div>
        </div>
    </div>
</body>

</html>